Alcohol is a clear, colorless liquid that is also known as ethanol or ethyl alcohol. This multifunctional ingredient is known well for its antimicrobial capabilities, as it is the most frequently used active ingredient in hand sanitizers. It is effective against a wide range of microbes, including bacteria, fungi, yeast, and even some viruses.
In addition to being an antimicrobial agent, alcohol also makes an excellent solvent. Water and oils do not typically mix well, but both can be dissolved into alcohol, which means they can be combined when they are otherwise incompatible.
Alcohol is also used as an astringent. An astringent is a type of ingredient that dries out and toughens up the skin surface, and alcohol is well-known for having this effect on skin.
Additionally, alcohol can serve as a viscosity controlling agent. When it is added to a skincare product, the product becomes thinner and less viscous. This is useful for decreasing the thickness of products that need to be sprayable, such as hairsprays or skin finishing mists.
Finally, alcohol can also reduce foaming activity where foaming is not desired, such as in emulsion-based products like creams and lotions.